France's EDF (EDF.PA), South Korea's KHNP, and U.S.-Canadian group Westinghouse Electric have made initial bids to build a new unit at the Czech Republic's Dukovany nuclear power plant, Czech utility CEZ (CEZP.PR) said on Wednesday.
The Czech Republic has been a strong backer of nuclear energy as a carbon-free power source for the future, unlike European Union neighbours Germany and Austria.
Majority state-owned CEZ, which launched the Dukovany expansion tender in March, said final bids would come in by the end of September 2023.
"We expect the contracts to be finalized in 2024," board member Tomas Pleskac said in a statement.
The 1,200 megawatt-unit should be completed in 2036 and help the country replace current Soviet-designed units at Dukovany that will eventually be decommissioned.
CEZ plans to build three more nuclear units - on top of the one now planned - at its Dukovany and Temelin nuclear sites, as the country diversifies away from coal. It is also planning to build smaller modular nuclear power plants.
Nuclear made up 36% of Czech energy output in 2021.
Candidates from China and Russia were excluded on security grounds, in contrast to Hungary which has chosen Russia's Rosatom for its nuclear project.
Poland picked Westinghouse last month to build its first nuclear power plant, and also agreed to cooperate with South Korea on potential further units.
The Czech government has been considering restructuring the 70% state-owned CEZ, the biggest listed firm in Prague with market capitalisation of $18.4 billion, in the coming years, which could lead to the state fully taking over the nuclear projects.
In 2020, the cost of the project - not including financing and inflation - was estimated at 6 billion euros ($6.2 billion). That was prior to the recent spike in global inflation and CEZ has not given an updated estimate.
Before power prices soared after Russia's invasion of Ukraine this year, the government agreed to provide interest-free financing for the project and to buy power from the plant at pre-determined prices derived from construction costs.